The remnants of Tropical Storm Ivo, off the coast of Baja, are pumping tropical moisture into the Southwest.

Tropical storm off Baja pumping moisture into Southwest

By Summit Voice

FRISCO — So far, the Atlantic hurricane season hasn’t been particularly active, but in the eastern Pacific, nine named storms have formed, most of them moving out to sea with little impact to land areas.

A broad swath of very dry air extends from the Pacific across the Desert Southwest in this June 26 NOAA satellite image.

By Summit Voice

SUMMIT COUNTY — Temperatures Wednesday soared to near-record levels in Frisco, topping out at about 80 degrees as an early summer high pressure system built into the Southwestern U.S. Average temperatures for most Summit County weather stations this time of year are in the mid-70s.

Excessive heat warnings from the National Weather Service covered a large area in Southern California and Southern Nevada, where Las Vegas reached a high of 117 degrees, busting the old record for the day by 2 degrees. There’s little relief in sight the next few days with the heatwave expected to continue. Continue reading “Weather: Southwest heatwave expands to Colorado”→

The Madden-Julian Oscillation has played a role in Colorado weather this winter.

By Summit Voice

FRISCO — With neither El Niño or a La Niña conditions in the Pacific Ocean, long-range weather forecasters have been struggling to develop confidence in their outlook for the coming spring season — a critical time for much of the West in terms of getting some relief from drought conditions.

A wet and cool spring could at least take the edge off the drought in some areas, helping to maintain stream flows and reduce the potential for massive and dangerous wildfires. Conversely, a return to last year’s very dry and warm spring pattern would spell trouble for places like Colorado.

The 8-14 day outlook from the Climate Prediction Center calls for a high chance of colder-than-average temperatures across much of the western and central U.S.

Forecasters warn of possible ‘Arctic outbreak’ in mid-January

By Summit Voice

FRISCO — A sudden stratospheric warming in the Arctic region may push extremely cold Arctic air into parts of the mid-latitudes during the next few weeks, according to forecasters with AccuWeather.com, who say the Arctic outbreak could start in the Pacific Northwest and then move into the northern Rockies and the central U.S.

Sudden stratospheric warming is considered by some meteorologists to be among the most dramatic atmospheric events, occuring when the westerly winds of the polar vortex slow down, or sometimes even stop and reverse direction. When the stratosphere, between 6 and 30 miles high, warms, it forces cold air to to build in the lower levels of the atmosphere and eventually surge southward. Continue reading “Weather: The big chill?”→

FRISCO — Jamaica is about to take a direct hit from what is now Hurricane Sandy, which is generating sustained winds of 80 mph just off the island nation’s southern coast. Hurricane warnings are in effect for the entire island, where six to 12 inches of rain is expected, leading to dangerous flooding.

Sandy’s storm surge will raise water levels by as much as one to three feet above normal along Jamaica’s southern and eastern coast, along with large and dangerous waves. Hurricane-force winds extend outward about 25 miles from the center of the storm, with tropical storm force winds extending outward up to 140 miles.

A hurricane warning is also in effect for most of eastern Cuba, where the storm surge could reach three to five feet along the southeastern coast. An even more intense storm surge of five to eight feet is expected in the Bahamas, where a hurricane watch is in effect.

Sandy will pass over Jamaica Wednesday afternoon and evening and reach Cuba Wednesday night and approach the Bahamas Thursday. Tropical storm conditions are possible along the southeast Florida coast Friday.

Beyond that, each subsequent forecast model has been pushing the storm closer to the East Coast, where emergency preparations have started. Some tracks show the storm interacting with an approaching cold front and hitting the North East as a powerful non-tropical storm, but the exact path is still uncertain.

Tropical Storm Nadine, the fifth-longest-lived storm on record in the Atlantic Basin. Map courtesy Supportstorm.Hurricane Nadine spins over the open waters of the Atlantic on Oct. 2, 2012. Satellite photo courtesy NASA.

Only four other storms have survived longer during the observed era

By Summit Voice

SUMMIT COUNTY — Most tropical weather systems make the news when they get really big and threaten coastal areas, but Tropical Storm Nadine, spinning near the Azores, will enter the record books as one of the longest-lived storms in the Atlantic Basin on record.

SUMMIT COUNTY — The trend of economically motivated weather forecasting by some pundits in the high country is just about as persistent as this summer’s monsoon rains have been. Most recently, the local newspaper took a stab at predicting Labor Day weekend weather about a week ago, calling for dry and sunny conditions.

Well, guess what? Labor Day weekend is here, and it looks like it might be a good idea to keep a rain jacket handy, as the showery pattern is likely to persist for the next few days.

“This is likely to continue until we see a major shift in the upper air pattern over the West,” the National Weather Service wrote in its daily weather discussion, and looking outside at the thunderstorms building over Buffalo Mountain suggests that forecast might be fairly accurate. Continue reading “Colorado: A weather rant”→